Understanding CMS Eligibility Checks: Why They Matter and How to Use Them Effectively
Eligibility verification is the foundation of smooth claims processing and timely reimbursement. One of the most essential tools for this is the CMS eligibility check — a process that confirms whether a patient is eligible for Medicare benefits under the Centers for Medicare & Medicaid Services (CMS).
Let’s explore what CMS eligibility checks are, why they’re important, and how providers can integrate them into their workflows using Electronic Data Interchange (EDI).
What Are CMS Eligibility Checks?
CMS eligibility checks verify if a patient is currently enrolled in Medicare, and if so, what type of coverage they have (Part A, B, C, or D). This includes information such as:
- Effective and termination dates
- Deductible and co-insurance details
- Primary vs. secondary payer status
- HMO or PPO enrollment (for Medicare Advantage)
These checks are typically conducted before rendering services to ensure coverage is active and to reduce the risk of claim denials.
How Are Eligibility Checks Performed?
Healthcare providers can access CMS eligibility information in several ways:
1. Online CMS Portals (like HETS)
2. Clearinghouses
3. Automated EDI transactions – specifically, the 270/271 transaction pair.
Example: EDI 270 Eligibility Request
ISA*00* *00* *ZZ*SENDERID *ZZ*CMS *240509*0915*^*00501*000000123*1*T*:~
GS*HS*SENDERID*CMS*20240509*0915*123*X*005010X279A1~
ST*270*0001*005010X279A1~
BHT*0022*13*10001234*20240509*0915~
HL*1**20*1~
NM1*PR*2*CMS*****PI*80840~
HL*2*1*21*1~
NM1*1P*2*YOUR CLINIC*****XX*1234567893~
HL*3*2*22*0~
NM1*IL*1*DOE*JANE****MI*123456789A~
DMG*D8*19450615*F~
DTP*291*D8*20240509~
SE*11*0001~
GE*1*123~
IEA*1*000000123~
This request sends patient and provider details to CMS to check eligibility for a particular date of service.
EDI 271 Response Sample (Simplified)
ST*271*0001*005010X279A1~
BHT*0022*11*10001234*20240509*0916~
EB*1**30**Health Benefit Plan Coverage**IND*Individual~
DTP*291*D8*20240509~
MSG*Patient is eligible for Medicare Part B~
The response confirms eligibility and outlines coverage type and applicable benefit info.
Why Eligibility Checks Matter
- Prevent claim rejections: Verifying CMS coverage before services avoids non-covered claim submissions.
- Improve cash flow: Clean claims submitted with accurate insurance data get reimbursed faster.
- Reduce manual work: Automating 270/271 transactions eliminates portal-based lookups.
- Enhance patient experience: Real-time checks give patients clarity about their financial responsibility.
Integration Tips
- Use real-time APIs or batch EDI via clearinghouses for 270/271 transactions.
- Regularly sync eligibility checks for recurring appointments.
- Confirm dual eligibility (Medicare + Medicaid) where applicable.
CMS eligibility checks are more than just a pre-visit formality – they’re a crucial part of revenue cycle management. Leveraging EDI tools like 270/271 not only improves efficiency but also ensures your practice gets paid accurately and on time. With smart integration, providers can reduce errors, save time, and focus more on patient care.
To learn more about EDI and become a CEDIAP® (Certified EDI Academy Professional), please visit our course schedule page.